This invention relates to a redundant storage system configured to add a guarantee code to write data to store the write data.
In a storage system, a redundant configuration of duplexing a controller is employed to improve fault tolerance. In the storage system having the redundant configuration, write data received by a primary controller is transferred to a secondary controller, and both the controllers write pieces of data to respective drives.
There is known a technology of adding a guarantee code (error check code) to data transferred from the primary controller to the secondary controller in order to guarantee consistency of the data in the above-mentioned storage system having the redundant configuration (for example, JP 5386593 B2).
In JP 5386593 B2, a processor of the primary controller adds a guarantee code to write data received from the host, and transmits the write data and the guarantee code to the secondary controller. A processor of the secondary controller acquires the guarantee code, and verifies the consistency of the transferred data.
As the guarantee code, there are known, for example, an LA/LRC, which combines a longitudinal redundancy check (LRC) for detecting a bit error and a logical address (LA) for detecting an error in address with each other.